4.2 How Minerals Form

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Vocabulary

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Solution- a mixture that has one substance that dissolves in another
Vein- a narrow channel, slab, or tube of mineral that's different from rocks that is lying around it

Outline

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Processes That Form Minerals

• Minerals form through crystallization either of melted materials or through crystallization of materials dissolved in water.
• minerals people use-formed deep in crust for a long time

Minerals From Magma

• affects size of crystals formed
  • rate magma cools
  • amount of gas contain
  • chemical composition (of magma)
• slow evaporation= large crystals

Minerals From Hot Water Solutions

• element form mineral-dissolve in hot water (sometimes)
• How minerals form by hot water solutions:

1. Magma heats water to a high temperature
2. Dissolved minerals form solutions
3. Hot water solutions cools,the elements and compounds leave the solution and crystallize to form minerals

• veins form by:
  • metals crystallize underground from solutions
• How minerals form from solutions along the mid-ocean ridge:
  1. ocean water seeps go down through cracks
  2. water meets high-temperature magma
  3. hot water dissolves minerals
  4. solution rises out chimneys
  5. hits cold
  6. crystallize

Minerals Formed By Evaporation

• minerals form when solution evaporates
• halite deposits
  • Midwest/Southwest
  • Gulf Coast
  • form when seas evaporate
• minerals form by evaporation of seawater:
  • gypsum
    • building materials
  • calcite
    • used in microscopes
  • minerals with potassium
    • fertilizer

Where Minerals Are Found

• crust mostly made of common rock-forming minerals
• valuable minerals
  • found in/near areas of volcanic activity/mountain building

Diagrams

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